Granted Patent
Utility
US 5,681,628 · App. 08/172,987
Pressurizable thermoplastic container having an exterior polyurethane layer and its method of making
Inventors:
Ken W. Niederst, John R. Zern, Jerome A. Seiner
Patented Case
View Patent ↗
Granted: Oct 28, 1997
Filed: Dec 27, 1993
Inventors
Ken W. Niederst
John R. Zern
Jerome A. Seiner
Assignee (at issue)
PPG Industries, Inc.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.